This invention relates to processing product components.
Product components can be intermixed to produce a wide variety of products having different physical characteristics. For example, a colloidal system may be a stable system comprising two immiscible substance phases with one phase dispersed as small droplets or particles in the other phase. Colloids may be classified according to the original phases of their constituents. For example, a solid dispersed in a liquid may be a dispersion. A semisolid colloidal system may be a gel. An emulsion may include one liquid dispersed in another.
For simplicity, we will call the dispersed phase xe2x80x9coilxe2x80x9d and the continuous phase xe2x80x9cwaterxe2x80x9d, although the actual product components may vary widely. Additional components may be included in a product such as emulsifying agents, known as emulsifiers or surfactants, that can stabilize emulsions and facilitate their formation by surrounding the oil phase droplets and separating them from the water phase.
As is described in U.S. Pat. No. 5,720,551, incorporated in its entirety, high pressure homogenizers are often used to intermix product components using shear, impact, and cavitation forces in a small zone. To prevent rapid wear to a high pressure homogenizer caused by different materials (e.g., relatively large solids), product components may be preprocessed by equipment such as ball mills and roll mills to reduce the size of such materials.
In general, in one aspect, a method of processing product components includes directing a first jet of fluid along a first path and directing a second jet of fluid along a second path. The paths are oriented to cause interaction between the jets that form a stream oriented essentially opposite to one of the jet paths.
Embodiments may include one or more of the following features. The first and second paths may oriented in essentially opposite directions. May be adjacent to one of the jets (e.g., a cylindrical stream surrounding one of the jets). The jets of fluid may be from a common fluid source. The jets may have identical or different jet characteristics. For example, the jets may have different velocities, for example, by ejecting the two jets at jet orifices of two different diameters.
In general, in another aspect, a method of processing product components includes directing a first jet of fluid from a common fluid source along a first path, directing a second jet of fluid from the common fluid source along a second path. The paths are oriented essentially opposite one another to cause interaction between the jets that forms a cylindrical stream surrounding one of the jets.
In general, in another aspect, a method of processing product components includes directing a first jet of fluid along a first path, directing a second jet of fluid along a second path, and causing sheer and cavitation in a third fluid by positioning the third fluid between the jets.
Embodiments may include one or more of the following features. The third fluid may include solids (e.g., powders, granules, and slurries). A gas may be used to position the third liquid.
In general, in another aspect, a method of processing product components includes directing a first jet of fluid formed from a common fluid source along a first path and directing a second jet of fluid formed from the common fluid source along a second path essentially opposite to the first path. The jets have different velocities and cause sheer and cavitation in a third fluid positioned between the jets. The jets form a stream oriented opposite one of the paths.
In general, in another embodiment, an apparatus for processing product components includes two nozzles configured to deliver jets of fluid along two different paths, and an elongated chamber that contains an interaction region in which the two paths meet. The chamber is configured to form a stream of fluid from the two jets that follows a path that has essentially the opposite direction from one of the paths of one of the jets.
Embodiments may include one or more of the following features. The apparatus may also include an outlet port configured to emit the stream. The nozzles may be aligned essentially opposite one another. The apparatus may also include an inlet port configured for receiving a second fluid. The inlet port may be aligned to position the second fluid such that the jets cause sheer and cavitation in the second fluid. The apparatus may also include a port that may be configured to be either an inlet port or an outlet port.
The chamber may include one or more reactors which may have different characteristics (e.g., inner diameter, contour, and composition). Seals may be positioned between the reactors. The seals may have different seal characteristics (e.g., inner diameter).
In general, in another aspect, an apparatus for processing product components includes two nozzles, aligned essentially opposite one another, configured to deliver respective jets of fluid along two different paths. The apparatus also includes an elongated chamber containing an interaction region in which the two paths meets. The chamber includes reactors and seals and is configured to form a stream of fluid from the two jets essentially the opposite direction from one of the paths of one of the jets. The apparatus further includes an outlet port configured to emit the stream.
Advantages of the invention may include one or more of the following. Very small liquid droplets or solid particles may be produced in the course of combining product components (e.g., emulsifying, mixing, blending, suspending, dispersing, de-agglomerating, or reducing the size of solid and/or liquid materials). Nearly uniform sub-micron or nano-size droplets or particles are produced. A broad range of product components may be used while maximizing their effectiveness by introducing them separately into the double-jet cell. Fine emulsions may be produced using fast reacting components by adding each component separately and by controlling the locations of their interaction. Control of temperature before and during product formation allows multiple cavitation stages without damaging heat sensitive components, by enabling injection of components at different temperatures and by injecting compressed air or liquid nitrogen prior to the final formation step. The effects of cavitation on the liquid stream are maximized while minimizing the wear effects on the surrounding solid surfaces, by controlling orifice geometry, materials selection, surfaces, pressure and temperature. A sufficient turbulence is achieved to prevent agglomeration before the surfactants can fully react with the newly formed droplets. Agglomeration after treatment is minimized by rapid cooling, by injecting compressed air or nitrogen, and/or by rapid heat exchange, while the emulsion is subjected to sufficient turbulence to overcome the oil droplets"" attractive forces and maintaining sufficient pressure to prevent the water from vaporizing.
Scale-up procedures from small laboratory scale devices to large production scale systems is made simpler because process parameters can be carefully controlled. The invention is applicable to colloids, emulsions, microemulsions, dispersions, liposomes, and cell rupture. A wide variety of immiscible liquids may be used in a wide range of ratios. Smaller amounts of (in some cases no) emulsifiers are required. The reproducibility of the process is improved. A wide variety of products may produced for diverse uses such as food, beverages, pharmaceuticals, paints, inks, toners, fuels, magnetic media, and cosmetics. The apparatus is easy to assemble, disassemble, clean, and maintain. The process may be used with fluids of high viscosity, high solid content, and fluids which are abrasive and corrosive.
The emulsification effect continues long enough for surfactants to react with newly formed oil droplets. Multiple stages of cavitation assure complete use of the surfactant with virtually no waste in the form of micelles. Multiple ports along the process stream may be used for cooling by injecting components at lower temperature. VOC (volatile organic compounds) may be replaced with hot water to produce the same end products. The water will be heated under high pressure to well above the melting point of the polymer or resin. The solid polymer or resins will be injected in its solid state, to be melted and pulverized by the hot water jet. The provision of multiple ports eliminates the problematic introduction of large solid particles into the high pressure pumps, and requires only standard industrial pumps. The invention also enables particle size reduction of extremely hard materials (e.g., ceramic and carbide powders).